The present invention relates to a syringe device wherein the needle cannula is inclinedly retracted into the barrel by pulling the plunger after the medicine in the tube is injected.
A conventional syringe device is shown in FIG. 1 and generally includes a barrel 10 with an engaging tube 12 extending from an end of the barrel 10. A stopper 17 is movably received in the barrel 10 and connected to a plunger 15 by a connection member 16 which is securely inserted into the stopper 17. A locking tip 180 is mounted to the engaging tube 12 and a needle cannula 181 is connected to the locking tip 180. Medicine in the interior 11 of the barrel 10 can be injected out from the needle cannula 181 by pushing the plunger 15 toward the engaging tube 12. A cap can be mounted to the locking tip to enclose the needle cannula 181. After being used, the syringe device has to be discarded and the needle cannula 181 together with the locking tip 180 are removed from the engaging tube 12. However, it is dangerous that when mounting the cap to enclose the needle cannula 181, the user could be cut by the needle cannula 181 and is therefore contaminated.
The present invention intends to provide a syringe device wherein the needle cannula is automatically retracted into the barrel by pulling the plunger away. from the needle cannular so that the users do not touch the needle cannula.
In accordance with one aspect of the present invention, there is provided a syringe device and comprising a barrel having an engaging section extending from a first end thereof. A hole is defined through the engaging section and a shoulder portion is defined in an inside of the first end of the barrel. A base member IS removably received in the engaging section and a tubular member extends from a first end of the base member and extending through the hole in the engaging section. A needle cannula is engaged with the tubular member. An engaging recess is defined in a second end of the base member and a first flange extends inward from a periphery defining the engaging recess. A stopper connected to a plunger is movably received in the barrel and a protrusion extends from the stopper. The protrusion is sized to engage with the engaging recess of the base member. A pushing means is located between the base member and the stopper so as to apply a force to the base member laterally when the base member is moved into the barrel when the plunger is pulled backward.
The primary object of the present invention is to provide a syringe device wherein the needle cannula is retracted into the barrel and a tip of the needle cannula contacts against the shoulder portion in the barrel.
These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, several embodiments in accordance with the present invention.